Planning for realm support

A realm is a collection of users from one or more LDAP trees from one or more user registry that form a coherent user population within IBM^® WebSphere^® Portal Express. A realm is then mapped to a Virtual Portal to allow the realm's user population to log in to the Virtual Portal.

For example, if you are an international company with employees in Asia, Europe, America, and Canada, you may have an application or information that only applies to a subset of these employees. You can create a subset of employees and create a Virtual Portal that contains the application or information for that realm. Users from one realm cannot access another realm unless they are also members of that realm. For example, the wpsadmin user will not be able to log in to a Virtual Portal unless the wpsadmin user is a member of the corresponding realm.

Important: When combining multiple user registries, you must ensure that the distinguished names are unique over all registries. For example, if wpsadmin exists in LDAP1, it cannot exist in LDAP2, LDAP3, or database user registry1. Also, the user must exist in a user registry and not within the property extension configuration; otherwise, they cannot be a member of the realm.